import 'package:flutter/material.dart';
import 'dart:async';

import 'package:flutter/services.dart';
import 'package:barcode_scan_plugin/barcode_scan_plugin.dart';

void main() => runApp(MyApp());

class MyApp extends StatefulWidget {
  @override
  _MyAppState createState() => _MyAppState();
}

class _MyAppState extends State<MyApp> {
  String _platformVersion = 'Unknown';
  String barcodeStr = '';
  @override
  void initState() {
    super.initState();
    initPlatformState();
  }

  // Platform messages are asynchronous, so we initialize in an async method.
  Future<void> initPlatformState() async {
    String platformVersion;
    // Platform messages may fail, so we use a try/catch PlatformException.
    try {
      platformVersion = await BarcodeScanPlugin.platformVersion;
    } on PlatformException {
      platformVersion = 'Failed to get platform version.';
    }

    // If the widget was removed from the tree while the asynchronous platform
    // message was in flight, we want to discard the reply rather than calling
    // setState to update our non-existent appearance.
    if (!mounted) return;

    setState(() {
      _platformVersion = platformVersion;
    });
  }

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      home: Scaffold(
        appBar: AppBar(
          title: const Text('Plugin example app'),
        ),
        body: Center(
          child: /*Text('Running on: $_platformVersion\n')*/ FlatButton(
              onPressed: (){
                scan();
              },
              child: Text('$_platformVersion')),
        ),
      ),
    );
  }

  Future scan() async {
    print('scaning....');
    try {
      String barcode = await BarcodeScanPlugin.scan();
      setState(() => this.barcodeStr = barcode);
    } on PlatformException catch (e) {
//      if (e.code == BarcodeScanner.CameraAccessDenied) {
//        setState(() {
//          this.barcode = 'The user did not grant the camera permission!';
//        });
//      } else {
//        setState(() => this.barcode = 'Unknown error: $e');
//      }
    } on FormatException{
      setState(() => this.barcodeStr = 'null (User returned using the "back"-button before scanning anything. Result)');
    } catch (e) {
      setState(() => this.barcodeStr = 'Unknown error: $e');
    }
    print('code = $barcodeStr');
  }

}
